User input devices for data processing systems are well-known and include various devices such as a mouse, keyboard, touch screen, etc. The term “click” is commonly used to refer to the action of pressing a mouse button (usually the left mouse button if the mouse has two buttons) or actuating other user input devices one or more times. For example, a click can also refer to user actions on a touch screen including a touch start action (finger down) and a touch end action (finger up). The actions performed when clicking a user input device depend on the particular computer or software program being used. Below are general ways to “click” a user input device and the corresponding actions performed.
A “single-click” often refers to pressing and releasing the button of a user input device (or finger down followed by finger up on a touch screen device) to perform various actions. A user can click on a particular on-screen button, menu, tool bar tab, icon, file menu, or other object in a graphical display, etc. For a mouse with two or more buttons, a single-click typically defaults to the left mouse button, which may also be referred to as “left-clicking” the mouse.
A “right-click” often refers to pressing an alternate mouse button (often the right one) to perform special actions or to bring up a selection menu with additional action options. For example, right-clicking a mouse button may bring up a menu with additional options relating to the particular object that was selected with the right-click. A “middle-click” often refers to pressing the middle button of a three-button user input device (such as a three-button mouse or using a mouse wheel as a third button) to perform pre-programmed options that can be configured through the user input device settings or a software program.
“Click-and-drag” often refers to pressing and holding the button of the user input device (or touching down and moving one's finger in the display screen of a touch screen device) while moving from one location to another. Click-and-drag, or for simplicity, “drag” operations can be used to highlight or select text (drag-select) or to select one or more objects. A “double-click” often refers to pressing a button of the user input device (or finger down on a touch screen device) two times in rapid succession. Typically a double-click user input can be used to open or execute files or programs, etc.
Zooming, panning and selecting are common user input functions available for dealing with large amounts of data in a graphical display. For example, many computer-aided design (CAD) programs, text processing software, and interactive charts include voluminous amounts of information that may not be easy for users to observe without the ability to zoom in/out, pan, and select objects at different locations within a file or program, or at different levels of granularity. To solve these issues, such programs offer the possibility to select and manipulate objects, and also enable users to zoom in/out of the graphical display.
However many such applications configured to display large amounts of information in a graphical display screen rely on additional menus, toolbars, and/or buttons to offer such functions. Relying on such menus, toolbars, and buttons is cumbersome and requires a significant amount of actions and movements to be taking with the user input device to initiate the desired functions. Moreover, for data processing devices that do not have access to a mouse, such as a laptop computer or a device having a touch screen, it is often challenging for users to zoom, pan, and select objects in the graphical display of these devices.